Electric switch



Jan. 17, 1933. ug- 1N 1,894,339

ELECTRIC SWITCH Original Filed June 1, 1928 Fig.4

OOOOOOOOO OOOOOOO y INVENIOR Arfhur 0 Ava/m TTORNEY ARTHUR 0. AUSTIN, FNEAR BARBERTON, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS,

Patented Jan. 17, 1933 UNITED STATES PATENT OFFIC TO THE OHIO BRASSCOMPANY, OF MANSFIELD, OHIO, A CORPORATION OF NEW JERSEY ELECTRIC SWITCHApplication filed June 1, 1928, Serial No. 282,215. Renewed February 10,1931.

This invention relates to high potential oil break switches and has forone of its objects the provision of an oil break switch which shall besimple and economical to manufacture and which shall be efficient inoperation. A further object is to provide an oil break switch in whichthe insulator bushings for the conductor leads will also serve asinsulation for the switch operating members. Other objects andadvantages will appear from the following description.

The invention is exemplified in the combination and arrangement of partsshown in the accompanying drawing and described in the followingspecification, and it is more particularly pointed out in the appendedclaims.

In the drawing:

Fig. 1 is an elevation with parts in section showing one embodiment ofthe present invention.

Fig. 2 is a fragmentary bottom plan view of a part of the switchoperating mechanism.

Fig. 3 is a fragmentary elevation of the connection between theconductor terminal and the switch operating mechanism.

Fig. 4 is a fragmentary top plan view substantially on line 4- -4 ofFig. 1.

Fig. is a horizontal section on line 5-5 of Fi .1.

igh voltage circuit breakers are a source of considerable expense andtrouble on large high voltage systems. In order to lower the cost ofmanufacture and to obtain improved operation of circuit breakers, I havedevised a new type of circuit breaker which has advantages over theordinary types for many cases.

In the form of the invention shown in the drawing, the high voltageleads 10 and 11 enter through bushings 12 and 13. The contactarms 14 and15 are attached to the lower end of the rods 16 and 17 respectivelyrunning through the bushings. The conductor rods 16 and 17 are free torotate in the bushings as they simply pass through the tubu-' laropenings formed by the metal tubes 18 in the bushing which is commonconstruction in many types.

The rotating conductors 16 and 17 are provided with weather caps 19 sothat water will be prevented entering the bushings. The rotating members16 and 17 are provided with arms 20 which are connected by links 21 toan arm 22 mounted on the top of rotating insulator stacks 23 and 24. Thelink mechanism connecting the rotating rods 16 and 17 is such that therotation of the insulator stacks 23 and 24 will cause the rods torotate.

The insulator stacks are provided with shafts 25 and 26 which, in turn,have shives 27 and 28 connected by cables or chains 29 and 30 to a drivepulley 31. The operation of the drive pulley rotates the insulatorstacks which, in turn, rotate the operating rods 16 and 17 so that thearms 14 and 15 may be made to advance or recede with respect to eachother.

The insulator stacks are comparatively inexpensive and easily installedcompared to the usual operating rods placed beneath the oil. Since theoperating mechanism is entirely outside of the oil circuit breaker case,the deterioration of the oil does not affect the insulation orperformance of these members. By using bushings which have internalscreens or internal current transformers 32, it is possible to providevery efficient insulation for all conditions.

If the oil level allows an insulating zone between the surface of theoil and the switch cover, it is possible to prevent any direct leakageat normal frequency over the surface of the bushing, even though the oilmay have a very low resistance. This insulating zone being screenedinternally by the current transformer 32 which acts as a flux control,as explained in my prior Patent 1,699,342 will not have a staticdischarge over the surface and may be used effectively to prevent acoating or carbonized path over the surface of the bushing due to theflow of current through oil or deposit on the bushing. With thisarrangement, much of the conducting material in the oil will settle tothe bottom of the tank, permitting an improvement in the insulatingvalue of the oil.

In the ordinary construction, where a meta1 sleeve projects down belowthe surface of the oil and materially reduces the path, conductingmaterial in the oil tends to build up and bridge the insulating surface.

The present type of construction also lends itself to installationswhere it is desired to eliminate an air space at the top above thesurface of the oil so as to prevent explosions. Where the entire case isfilled with oil, an expansion of the oil due to a rise in temperature ordue to an opening of a heavy arc might set up a pressure which wouldrupture the tank or container. This difficulty has been provided for inmy previous application Number 7 22,204 filed June 25, 1924, in which anexpansion chamber 40 is provided with an opening below the surface ofthe oil. This expansion chamber may run entirely around the case or beof any suitable form such that the flow of the oil due to thecompression of the air or glands 41 in the expansion chamber, will notbe affected by the inertia of the oil. 7

, With this class of construction the length of the bushings may begreatly reduced. This permits of a smaller tank, all of which tends toreduce the cost of the circuit breaker.

It is evident that various forms of contact members may be used andabsorbing baffles may be attached to the bushings or to the tank tobreak up large pockets of hot gas. The contact members may be providedwith an expansion chamber as in common practice 7 in some bushings orwith a multiplicity of contacts operating in multiple or in series so asto provide a long eflective resistance in the path of the are quicklyand so as to break up large pockets of hot gas in order that the heatgenerated may be readily absorbed by the oil without danger of causingan arc to ground.

The contact arms may be attached to conducting rods which haveconsiderable torsional resilience so that when the switch is in closedposition, there will be a considerable torsional displacement in thecontact members or in the springs forming the contact arms or betweenthe contact arms and the conducting rods. When the parts are placedunder stress by the closing action of the switch, a slight additionalmovement on the part of the operating insulator stacks or rods throughthe bushings will permit of one contact member sliding past the otherand a ql ick opening of the switch resulting from the stored energy inthe conductor rods due to their torsional displacement. It is evidentthat this release may be afiected magnetically either by the currentflowing through the bushing or at any point in the conducting mechanism,or by an external circuit operating through a current transformerincorporated in the bushing or in the circuit outside of the bushing.

I claim:

1. The combination with a housing, of a pair of bushing insulatorsextendingthrough the wall of said housing, conductor rods extendingthrough said insulators, laterally extending contact arms connected withsaid respective conductor rods within said housing and arranged tocontact with each other to form electrical connection between saidconductor rods, and means for simultaneously rotating said conductorrods to move said contact arms together from opposite directions. 7 Y

2. A high potential switch comprising a housing, a bushing insulatorextending through the wall of said housing, an operating rodextendingthrough said bushing insulator and rotatably mounted therein, a

switch contact connected with said rod'withinsaid housing, and insulatedmeans connected' with said rod outside of said housing for rotating saidrod, there being resilient yielding connection between said rotatingmeans and said switch contact. r

3. A high potential switch comprising a housing, a bushing insulatorextending through the wall of said housing, a switch contact disposedwithin said housing, an operating rod rotatably mounted in said bushinginsulator and secured to said switch contact, an operating arm connectedwith said rod outside of said housing, said arm having a socket'forreceiving theend of said rod provided with an imperit'orate cover forthe end of said rod and having a flange over.- lapping the openingthrough which said rod projects from said insulator to exclude waterfrom said insulator, and a conductor electrigally connected with theouter end of said ro 4. In a high potential switch comprising an oilcontaining housing, a pair of bushing insulators extending throughthewall of said housing, operating rods rotatably mounted in saidbushing insulators respectively, switch contacts carried by saidoperating rod and movable into and out of contact with each other whensaid rods ar rotated, and insulated operating means for rotating saidrods disposed outside of said housing.

5. A high potential switch comprising an oil containing housing, a pairof bushing insulators extending through'the wall of said housing andfixed thereto, combined operating rods and conductor leads extendingthrough said bushingiinsulators and rotatably mounted therein, contactarms secured to the inner ends of. said combined rods and leads andarranged to engage each other, and operating means for rotating saidrods to bring said contact arms into engagement when moved together fromopposite directions, the connection between said contact arms andoperating mechanism having sufficient resiliency to permit saidconnection to be placed under resilient stress and to permit saidcontact arms to pass each other when the connection is so stressed toeffect quick disconnection of said arms.

6. A high potential switch comprising an oil containing housing, a pairof bushing insulators extending through the top of said housing andfixed thereto, operating rods extending through said bushing insulatorsand rotatable therein, contact arms secured to said rods within saidhousing and arranged to engage each other at a point below the surfacelevel of the oil within said housing, insulated means outside of saidhousing for rotating said rods to effect contact of said arms, theconnection between said arms and operating means having suflicientresiliency to permit said arms to pass when placed under stress by saidrotating means and thus to effect quick separation of said arms.

7. A high potential switch comprising an oil containing housing, a pairof bushings extending through the top of said housing and fixed thereto,a rod extending through said bushings and rotatable therein, saidcontacts secured to the inner ends of said rods respectively, operatingarms secured to the outer ends of said rods respectively, rotatableshafts having insulating sections connected with said operating arms,and means for rotating said shafts to move said arms and 0p erate saidswitch contacts through the rotation of said rods.

8. An electric switch comprising a housing, a bushing insulatorextending through the wall of said housing and having its longitudinalaxis in fixed position relative to said housing, a contact membersupported by said bushing insulator, operating means for said contactmember arranged to rotate said contact member about the axis of saidinsulator, and a yielding connection between said operating means andcontact member arranged to be placed under stress by said operatingmeans to effect quick movement of said contact member by the energystored in said connection when under stress.

9. A switch comprising a pair of contact members, means for moving oneof said contact members into contact with the other to close saidswitch, yielding means for exerting further force on said contact in thedirection of its closing movement, said yielding means being placedunder stress by said force, one of said contacts being arranged to yieldto the other to permit said contacts to pass and open said switch byrelative movement in the same direction as the closing movement and byquick action under the stress in said yielding means.

10. In an electric switch, a rotatable operating member, a switch bladeextending laterally from the axis of said member and having a contactportion spaced from the axis of said member, resilient connectionbetween said contact portion and operating member, a cooperatingcontact, means for holding said operating member in a position to placesaid resilient connection under stress when said contact portion andcooperating contact are in engagement and when said switch is closed,said yielding connection being arranged to permit said contact portionto pass said cooperating contact when additional stress is placed uponsaid resilient connection by said operating member.

11. In a quick acting electric switch, a pair of rotatable operatingmembers, switch blades extending laterally from the axes of saidoperating members respectively and having contact portions arranged toengage each other at a point between the axes of rotation of saidoperating members, there being yielding connection between saidoperating members and the respective contact portions of said blades,said yielding connections being placed under stress when said switch isclosed and said blades are in operating engagement, said yieldingconnections being arranged to permit said blades to pass each other whenadditional stress is placed upon said yielding connections by saidoperating members.

12. In an electric switch, a rotatable operating rod, a bushing throughwhich said rod extends, an operating arm secured to the end of said rodabove said bushing, said operating arm having an imperforate weathershed covering the upper end of said bushing.

In testimony whereof I have signed my name to this specification this26th day of May A. D. 1928.

ARTHUR O. AUSTIN.

